The present invention relates to a conveyor belt roll assembly and specifically to one comprising a roll casing, a roll end made of sheet metal mounted in each end of the roll casing, each roll end supporting a rolling bearing with at least one bearing ring made of sheet metal in the bore of the roll casing and a shaft, the other bearing ring for the rolling bearing being secured in an axial direction by means of a ring member connected to the shaft.
Conveyor belt rolls generally of the type described above are known wherein the roll end and at least one of the bearing rings are made of relatively thin walled sheet metal. In these known assemblies the sheet metal bearing ring is usually constructed as a spherical shell shaped recess of the roll end. An assembly of this type is illustrated in German Patent DE-Gbm No. 1 992 970.
Conveyor belt rolls are also known which include a bearing ring made of thin walled sheet metal having a radial flange formed integrally therewith which forms the roll end and by which the bearing is secured in the bore of the roll casing. German Patent DE-AS No. 1 273 916 and DE-Gbm No. 7 334 209 show arrangements of this type wherein the bearing ring carries the outer race of the rolling elements and German Patent No. DE-Gbm No. 7 731 602 shows an assembly wherein the bearing ring carries the inner race of the rolling elements.
In these prior known constructions, the roll end or the flange of the bearing which forms the roll end is formed in a flat manner and acts as a diaphragm which has a comparatively low rigidity. The roll end in these constructions is connected with the roll casing by means of a welded seam. This welded seam is relatively long and thus requires a considerable amount of welding material and in addition a relatively long and complicated welding procedure. In order to axially secure the roll casing in relation to the shaft, a snap ring is usually used which seats in an annular groove located in the inside area of the roll. This construction presents certain disadvantages. For example, the groove weakens the shaft and furthermore it is located in an inaccessible, difficult to reach location. Furthermore, these known arrangements have practically no sealing ability at all which means the inside bearing space is not protected as well as it should be to prevent escape of lubricant and ingress of foreign matter which can cause deterioration or failure of the bearing especially in dust and dirt-laden environments.
To combat this condition, it is previously known to provide special seals in front of the bearing such as labyrinth seals. These seals, however, increase the axial length on the one hand and complicate the assembly process by reason of the separate parts required.